Seattle Mayor Ed Murray has announced plans to resign following multiple accusations of sexual abuse after a fifth accuser -- who is the mayor's younger cousin -- came forward and alleged that Murray repeatedly molested him in the 1970s.

Murray, 62, announced Tuesday that he will step down effective 5 p.m. Wednesday.

The mayor had already said that he wouldn't seek a second term.

Accuser Joseph Dyer, who is a dialysis technician and Air Force veteran, says the molestation occurred in New York when he was a teen, according to The Seattle Times.

The 54-year-old Dyer — Murray's first cousin once removed — told the newspaper that he wants the mayor punished for the alleged actions, saying, "I have had enough. ... Something has got to be done."

Murray has denied the accusation, attributing it to a longstanding family schism.

"While the allegations against me are not true, it is important that my personal issues do not affect the ability of our City government to conduct the public's business," the mayor said in a statement.

Dyer reportedly said the incidents occurred when he was 13, while Murray, who was then in his early 20s, shared a bedroom with Dyer in his mother’s Long Island home.

"There would be times when I would fake sleeping because I didn't want him touching me," Dyer told the newspaper.

Four men had previously accused Murray of sexually abusing them. Murray has denied all of the allegations.

Before being elected mayor in 2013, Murray was a long-time Democrat state lawmaker who led the campaign to legalize same-sex marriage in Washington state.

As mayor, Murray pushed to raise the city's minimum hourly wage to $15.

"To the people of this special city and to my dedicated staff, I am sorry for this painful situation," Murray said.

Fox News' Frank Miles and The Associated Press contributed to this report.